51121601 has 4 divisors (see below), whose sum is σ = 54128772. Its totient is φ = 48114432.

The previous prime is 51121597. The next prime is 51121613. The reversal of 51121601 is 10612115.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 31629376 + 19492225 = 5624^2 + 4415^2 .

It is a cyclic number.

It is not a de Polignac number, because 51121601 - 2² = 51121597 is a prime.

It is a super-2 number, since 2×51121601² = 5226836177606402, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (17), and also a Moran number because the ratio is a prime number: 3007153 = 51121601 / (5 + 1 + 1 + 2 + 1 + 6 + 0 + 1).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 51121601.

It is not an unprimeable number, because it can be changed into a prime (51121501) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1503560 + ... + 1503593.

It is an arithmetic number, because the mean of its divisors is an integer number (13532193).

Almost surely, 2^51121601 is an apocalyptic number.

It is an amenable number.

51121601 is a deficient number, since it is larger than the sum of its proper divisors (3007171).

51121601 is a wasteful number, since it uses less digits than its factorization.

51121601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3007170.

The product of its (nonzero) digits is 60, while the sum is 17.

The square root of 51121601 is about 7149.9371325907. The cubic root of 51121601 is about 371.1374807425.

Adding to 51121601 its reverse (10612115), we get a palindrome (61733716).

The spelling of 51121601 in words is "fifty-one million, one hundred twenty-one thousand, six hundred one".